Marine growth cutting attachment for outboard motors



J. H. WISER March 27, 1956 MARINE GROWTH CUTTING ATTACHMENT FOR OUTBOARD MOTORS Filed Aug. 15, 1952 2 Sheets-Sheet 1 J J v INVENTOR Joseph H. I l/Zser ATTORNEYS March 27, 1956 J. H. WISER 2,739,435

MARINE GROWTH CUTTING ATTACHMENT FOR OUTBOARD MOTORS Filed Aug. 15, 1952 2 Sheets-Sheet 2 i6 QC) INVENTOR Jeph H. Vl/E'ser E GROWTH currmo ATTACHlt lENT FUR OUTBOARD MOTORS This invention relates to an under water mowing assembly attachable to an outboard motor and adapted for mowing grass, weeds, lily pads, and the like, in lakes or ponds.

It is well appreciated that bodies of water of the type referred to often become clogged with under Water and surface growth, making navigation diflicult and contributing to an unsanitary condition.

Heretofore, devices have been conceived adapted speciflcally for cutting submarine and surface growth. However, there has not heretofore been proposed, to my knowledge, an assembly of the type described adapted specifically as an attachment to an outboard motor, and arranged to be powered by said motor.

The broad object of the present invention is to provide an assembly having these novel characteristics.

A more specific object of the invention is to provide a device of the character referred to which, by reason of a novel construction embodied therein, can be secured with maximum ease and facility to the propeller shaft of an outboard motor, in substitution for the propeller usually mounted on said shaft.

Another object of importance is to provide a mowing assembly as stated which, by reason of the manner in which it is attachable to an outboard motor, can be constructed at a cost substantially lower than that required for manufacture of the ordinary marine growth cutting machine.

Still another object is to provide an assembly of the character referred to, which when attached to an outboard motor, will not affect adversely the normal operation of said motor, and will not require removal of said motor from its customary location upon the transom of a boat.

Yet another object is to provide a mowing assembly as stated which will be rugged, efficient in operation, and formed of a minimum of parts simply arranged in a manner whereby they will not readily get out of order.

Other objects will appear from the following descrip tion, the claims appended thereto, and from the annexed drawings, in which like reference characters designate like parts throughout the several views, and wherein:

Figure l is a side elevational view of a marine growth cutting assembly formed in accordance with the present invention as it appears when mounted upon an outboard motor, a portion of the assembly being cut away, a boat on which the motor is mounted being illustrated fragmentarily; v

Figure 2 is a sectional view taken on line 2-2 of Figure 1;

Figure 3 is an enlarged section taken longitudinally through the device per se, a portion of the shaft of said device being cut away; and

Figure 4 is a top plan view of the device.

Figure 5 is a fragmentary view, partly in section and with parts broken away, of the lower end of the propeller housing and the support plate of the mowing device of the present invention of the assembly in Figure l.

The reference numeral 10 has been applied generally to a boat on which is mounted a conventional outboard motor designated generally at 12. The mowing device constituting the present invention has been designated generally at 14, and as may be noted from Figure 1, is mounted upon the lower end of the propeller shaft housing 13 of the outboard motor.

The invention includes a support plate 16 formed as a casting having a concavo convex body integral throughout its periphery with an upstanding outer flange 18. Inner flanges 20, 22 respectively are integral at their ends with opposite sides of the flange 18, said flange 18 having, at locations spaced peripherally thereof, bosses 25 apertured as at 26 to receive connecting bolts, not shown, whereby the support plate can be fixedly connected to the lower end of a propeller shaft housing of an outboard motor.

it may be noted from Figure 4 that the support plate to, in the present instance, is of approximately elliptical shape when viewed in top plan. In this connection, the illustrated support plate is formed complementarily to the lower end of the propeller shaft housing of the illustrated motor 12, said housing also being of generally elliptical cross section at its lower end. The flanges 18, 20, 22 similarly complement portions of the propeller shaft housing, and the apertures 26 are all located so as to receive the bolts normally connecting the propeller housing to the propeller shaft housing.

Similarly, the support plate 16, as shown from Figure 3, has at its opposite ends upstanding aligning pins 24, projecting above the upper edge of the flange 18 into complementary openings of the propeller shaft housing, said openings normally receiving aligning pins provided upon the propeller housing of the motor.

it will thus be seen that the support plate 16 is mounted in place simply by removal of the conventional propeller housing and propeller, insertion of pins 24 in the aligning or pin holes 24' provided in the lower end of the propeller shaft housing 13, and extension of the connecting bolts 27 through the apertures 25 and threadedly engaging the threadedaperture 13' formed in the lower end of the prope'ller housing 13.

Outboard motorsrdiffer, vof course, All their particular shapes and sizes, and it will be understood that the support plate 16 can be varied as desired, for mounting on particular motors, it being mainly essential that the support plate be detachably and fixedly connectible to the lower end of the propeller shaft housing of its associated motor merely by removal of the ordinary propeller housing and propeller.

Formed in the centrally depressed body of the support plate 16 is a center opening 28, into which may be slidably inserted a sleeve bushing 30 externally threaded as indicated by the numeral 31 for substantially its full length and formed integrally, at its upper end, with a peripheral lip 32. engaging against the edge portion of the center opening 28.

A washer 34 is circumposed about the body of the bushing 30, and underlies the support plate in, after which a nut 36 is threaded upon the bushing in the direction of the support plate so as to hold the bushing in place Within the center opening.

The device includes a relatively elongated shaft 38, integrally or otherwise rigidly formed at its upper end with an enlarged, splined head iii. The head 40 is drivingly connected to a complemental splined head 43 carried by the lower end of the propeller shaft 45 by means of the coupling 47.

When the shaft 38 is separably connected to the propeller shaft of the motor for rotation jointly therewith, the propeller shaft of the motor will of course prevent upward movement of the shaft 38 relative to the support plate 16. The head 40, meanwhile, engages the bushing 30 at the lower end of said head, to prevent downward vertical movement of the shaft 38.

Carried by the lower end of the shaft 38 is a knife 42, said knife being formed, as shown in Figure 2, of oppositely extended, elongated, knife members rigidly con nected at their inner ends by a flat disc portion, said disc portion having a smooth walled opening 44 loosely receiving the threaded lower end of shaft 38.

A disc member 46 has a threaded center opening engaged with the threads at the lower end of shaft 33, an overlies the center portion of the rotary knife 42. A shear pin 48 is extended through the marginal areas of the disc portion of the knife 42, and the disc member 46, to connect the knife to the disc member 46 for rotation jointly therewith and with the shaft 38. It will be understood that should some obstruction be encountered by the knife during its rotation, the pin 48 will shear, to prevent damage to the motor.

Overlying the disc member 46 is a lock nut 56, threaded downwardly upon the lower portion of the shaft 3% into engagement with the disc member. A washer 52 underlies the knife 42, and threaded upwardly thereagainst is a lock nut 54, said lock nut being held against rotation from its locking position by means of a cotter pin 56 extended through a transverse opening formed in the lower end of the shaft 33.

It will be readily appreciated that the mowing device constituting the present invention can be attached to a conventional outboard motor with maximum speed and facility, without necessity of modifying or redesigning said motor. It will be further apparent that it is merely necessary, to mount the device, that the propeller mechanism be removed from the lower end of the propeller shaft housing, after which the device is readily secured in place, in the position shown in Figure 1. Thereafter, normal operation of the outboard motor will be effective to rotate the rotary knife 42 at high speed, so as to efficiently cut various types of marine growth.

It is believed clear that the invention is not necessarily confined to the specific use or uses thereof described above, since it may be utilized for any purpose to which it may be suited. Nor is the invention to be necessarily limited to the specific construction illustrated and described, since such construction is only intended to be illustrative of the principles of operation and the means presently devised to carry out said principles, it being considered that the invention comprehends any minor change in construction that may be permitted within the scope of the appended claims.

What is claimed is:

A marine growth cutting device adapted for attachment to a motor having a housing, a shaft extending within the housing, bolts extending from the housing, and aligning openings formed in the housing, comprising: an approximately elliptically shaped support plate formed as a casting having a concave-convex body, said casting being formed with arr-upstanding outer flange integral with the body throughout the periphery of the body, and with upstanding inner reinforcement flanges integral at their ends with the outer flange, said outer flange having a series of bosses spaced peripherally thereof and apertured to receive said bolts for fixedly connecting the support plate to said housing, said casting being additionally formed with upstanding aligning pins extending above the several flanges and adapted to project into said aligning openings,

said body having a center opening; a sleeve bushing extendthrough said center opening, said bushing including a peripheral lip at one end engaging against the body, the bushing being threaded at its other end; a nut threaded on said other end of the bushing to cooperate with the lip in engaging the body therebetween; a shaft journaled in the bushing, said last-named shaft having the major part of its length depending from the support plate and being formed above the support plate with a splined head for conmeeting the shafts in driving relationship, said head being enlarged in diameter relative to the diameter of the secondnamed shaft and engaging against said lip; and knife means mounted on the depending portion of the second-named shaft.

References Cited in the file of this patent UNITED STATES PATENTS 1,200,096 Firman Oct. 3, 1916 1,611,778 Rathke Dec. 21, 1926 2,319,947 Oswood May 25, 1943 2,518,093 Sutter Aug. 8, 1950 2,635,406 Chauvin Apr. 21, 1953 OTHER REFERENCES Popular Science, April 1950, page 1 17. 

